Microflow analytical system

ABSTRACT

A microflow analytical system includes a laminate pump assembly connectable with one or more sources of fluid, one or more pneumatic control pumps, a mixer, and a sensor. The laminate pump assembly is adapted to deliver predetermined volumes of the fluid(s) through a plurality of flow paths which are formed within layers of the assembly. Each flow path can include an inlet valve, a pump valve, and an outlet valve each of which are controllable by the pneumatic control pumps. A series of manifolds can be formed within the layers of the pump assembly to provide for simultaneous activation of selected flow paths. Delivered fluid volumes can be mixed in the mixer which, in some embodiments, may be integral with the laminate pump assembly. The sensor can measure one or more characteristics of the mixed fluids to determine one or more properties of the fluids.

FIELD

This disclosure generally relates to a microflow analytical system forperforming automated chemical analysis. In particular, this disclosurerelates to a microflow analytical system for determining theconcentration of a peracid and peroxide within a use composition.

BACKGROUND

An analytical procedure in chemistry consists of a series of operationscarried out in fixed sequence which may be considered steps or stages.One step in chemical analytical procedure often involves the delivery ofpredetermined volumes of one or more fluid chemicals. When performed byhand, analytical chemistry procedures can produce varied results due toa number of factors such as, for example, the usage of an improper orinaccurate volume of a fluid chemical. Moreover, manual analyticalchemistry procedures can be tedious and time consuming. Accordingly,there is a desire to automate analytical chemistry procedures.

One application of analytical chemistry is to determine theconcentration of one or more analytes within a composition. For example,the analytical chemical procedures can be useful in the analysis andmonitoring of antimicrobial compositions. Antimicrobial compositions areused in a variety of automated processing and cleaning applications toreduce microbial or viral populations on hard or soft surfaces or in abody or stream of water. For example, antimicrobial compositions areused in various applications including kitchens, bathrooms, factories,hospitals and dental offices. Antimicrobial compositions are also usefulin the cleaning or sanitizing of containers, processing facilities orequipment in the food service or food processing industries, such ascold or hot aseptic packaging. Antimicrobial compositions are also usedin many other applications including but not limited to clean-in-placesystems (CIP), clean-out-of-place systems (COP), washer-decontaminators,sterilizers, textile laundry machines, filtration systems, etc.

Whatever the application, an antimicrobial or “use” composition is acomposition containing a defined minimum concentration of one or moreactive components which exhibit desired antimicrobial properties. Onesuch category of active antimicrobial component are peracids, such asperoxycarboxylic acid (peracid), peroxyacid, peroxyacetic acid,peracetic acid, peroctanoic acid, peroxyoctanoic acid and others.

The concentration of active components in the use composition is chosento achieve the requisite level of antimicrobial activity. In usecompositions in which one or more peracids are the active component, andin the instance of a recirculating process, the concentration ofhydrogen peroxide tends to increase over time while the concentration ofperacid decreases. However, in order to maintain the requisite level ofantimicrobial activity, the amount of peracid in the use compositionmust be maintained at a defined minimum concentration. In addition, asthe amount of hydrogen peroxide in the use composition increases, theuse composition may exceed a defined maximum concentration of hydrogenperoxide in the solution. In some applications, for example bottlingline cleansing, the allowable amount of residual hydrogen peroxide issubject to government regulations. Once the hydrogen peroxideconcentration exceeds the maximum concentration, the spent usecomposition is discarded and a new use composition generated.

To ensure that the amount of peracid is maintained at or above someminimum concentration and to determine when the amount of hydrogenperoxide reaches or exceeds a maximum concentration, it is necessary todetermine the concentration of peracid(s) and hydrogen peroxide in theuse composition. In the past, to determine both the peracidconcentration and the hydrogen peroxide concentration in a usecomposition has required multiple time consuming manual titrations,several different reagents and relatively large volumes of usecomposition. Moreover, past devices and methods for determining bothperacid and hydrogen peroxide concentrations were effective over only anarrow range of concentrations.

SUMMARY

In a first aspect, a microflow analytical system is disclosed.Embodiments of the microflow analytical system include a laminate pumpassembly adapted to control parallel delivery of a plurality of fluids,a pneumatic control pump for controlling the delivery of fluids throughthe laminate pump assembly, a mixer for mixing the delivered fluids, anda sensor configured to obtain response data indicative of acharacteristic of the mixed fluids. The laminate pump assembly caninclude a plurality of flow paths formed therewithin. Each flow path ofthe laminate pump assembly includes a pump valve, an inlet valve, and anoutlet valve. The inlet valve can be connected to selectively providefluid communication between an inlet connector and the pump valve. Theoutlet valve can be connected to selectively provide fluid communicationbetween the pump valve and an outlet channel. Each of the pump valve,inlet valve, and outlet valve can comprise a chamber formed at aninterface of two layers of the laminate pump assembly. A pneumaticallyactuated membrane divides the chamber into a fluid flow cavity and apneumatic control cavity such that the delivery or removal of apneumatic fluid to the pneumatic control cavity can be used to controlthe valves. For example, delivery of a pneumatic fluid to the pneumaticcontrol cavity can cause the fluid flow cavity to collapse, therebyblocking the flow path and forcing fluid within the fluid flow cavityout along the flow path. Removal of pneumatic fluid from the pneumaticcontrol cavity can likewise cause the fluid flow cavity to open, therebydrawing fluid within the flow path into the fluid flow cavity andpermitting fluid flow through the flow path.

In another aspect, a method for measuring a concentration of one or moreanalytes within a use composition is disclosed. The method can includeproviding a laminate pump assembly adapted to control the delivery ofvolumes of a plurality of fluids, a mixer, and a sensor. The laminatepump assembly can include a plurality of flow paths formed therewithin,each flow path comprising a plurality of microfluidic valves adapted todeliver a metered fluid flow from an inlet connector of the flow path toan outlet channel of the flow path. The mixer can be connected in fluidcommunication with the outlet channels of the laminate pump assembly andadapted to mix fluid delivered from two or more of the flow paths. Thesensor can be coupled with the mixer and configured to obtain responsedata indicative of a reaction of the mixed fluids. The method furtherincludes connecting a source of the use composition and a source of atleast one reagent with the inlet connectors. The laminate pump assemblycan then be activated, thereby causing metered volumes of usecomposition and reagent to be delivered to the mixer. The meteredvolumes of use composition and reagent can then be mixed. The methodfurther includes obtaining response data from the sensor indicative ofthe concentration of the one or more analytes within the usecomposition. The concentration of the one or more analytes can then becalculated based on the response data.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are illustrative of particular embodiments of theinvention and therefore do not limit the scope of the invention. Thedrawings are not to scale (unless so stated) and are intended for use inconjunction with the explanations in the following detailed description.Embodiments of the invention will hereinafter be described inconjunction with the appended drawings, wherein like numerals denotelike elements.

FIG. 1 is a schematic of a microflow analytical system according to someembodiments.

FIG. 2 is a schematic view of an implementation of a laminate pumpassembly according to some embodiments.

FIG. 3A is a partially transparent, top plan view of a laminate pumpassembly according to some embodiments.

FIG. 3B is a top plan view a flow path of the laminate pump assembly ofFIG. 3A according to some embodiments.

FIG. 3C is a cross-sectional view of a flow path of the laminate pumpassembly of FIG. 3A taken along line C-C.

FIG. 3D is a cross-sectional view of the laminate pump assembly of FIG.3A taken along line D-D.

FIG. 3E is an enlarged sectional view of region 3E identified in FIG.3C.

FIG. 3F is a partially transparent, top plan view of a laminate pumpassembly adapted for use with a peracid and/or peroxide concentrationmonitor according to some embodiments.

FIG. 3G is a cross-sectional view of the laminate pump assembly of FIG.3F taken along line G-G.

FIG. 4A is a cross-sectional view of an “open” pneumatically actuateddiaphragm valve according to some embodiments.

FIG. 4B is a cross-sectional view of a “closed” pneumatically actuateddiaphragm valve according to some embodiments.

FIG. 5 is a flow chart illustrating a pump cycle activation sequenceaccording to some embodiments.

FIG. 6 is a schematic illustrating a pneumatic control pump connectionscheme according to some embodiments.

FIG. 7 is a cross-sectional view of a laminate pump assembly having anoptical sensor coupled directly thereto according to some embodiments.

FIG. 8 is a cross-sectional view of a laminate pump assembly having anincorporated sensor according to some embodiments.

FIG. 9A is a perspective view of a disposable bag reservoir according tosome embodiments.

FIG. 9B is a partial cross-sectional view of the disposable bagreservoir of FIG. 9A taken along line B-B.

FIG. 9C is an exploded, top perspective view of a disposable bagreservoir cartridge according to some embodiments.

FIG. 9D is an exploded bottom perspective view of the disposable bagreservoir cartridge of FIG. 9C.

FIG. 10A is a top plan view a flow path of a laminate pump assemblyaccording to some embodiments.

FIG. 10B is a cross-sectional view of the flow path of FIG. 10Aaccording to some embodiments.

FIG. 11 is a schematic view of a reversible pneumatic control pumpaccording to some embodiments.

FIG. 12 is a flow chart illustrating an exemplary control operation fora peracid/peroxide concentration sensor according to some embodiments.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 shows a schematic of a microflow analytical system 100 accordingto some embodiments. The system 100 includes a laminate pump assembly110 comprising a plurality of layers that define actuatable flow paths.The laminate pump assembly 110 is adapted to control the paralleldelivery of a plurality of fluids from fluid sources (e.g. usecomposition input 120, and/or fluid reservoirs 125) to analyticalinstrumentation. One or more pneumatic control pumps 130 can be coupledwith the laminate pump assembly 100 to selectively actuate microflowvalves formed therewithin, and thereby control the flow of fluid throughthe laminate pump assembly 100. In some embodiments, the analyticalinstrumentation comprises a mixer 140 and a sensor 150. In such systems,the sensor 150 can obtain response data indicative of characteristics ofthe mixed fluids. This response data can then be processed by aprocessor 160 to determine characteristics of properties of one or moreof the fluids.

Microflow analytical systems, according to some embodiments, enable theautomation of manual wet chemical analytical procedures. For example,the microflow analytical system 100 can be configured as a usecomposition monitor. A use composition monitor may be connected to asource of use composition 120, to monitor characteristics of the usecomposition such as, for example, the content or concentration ofselected analytes. In particular, some embodiments are well suited foruse as a use composition monitor for determining the concentration ofperacid and/or hydrogen peroxide in a use composition. For example, theuse composition may be monitored to ensure that the concentration ofperacid satisfies at least a minimum threshold concentration. The usecomposition may also be monitored to determine when the concentration ofhydrogen peroxide exceeds a maximum threshold concentration. Of course,embodiments of the microflow analytical systems disclosed herein shouldnot be limited to monitoring devices, for example, such systems can beused as analytical instruments or for other purposes.

In the embodiment shown in FIG. 1, the microflow analytical system 100includes a laminate pump assembly 110 under control of a controller 160.The laminate pump assembly 110 controls the parallel delivery of fluidsfrom connected fluid sources 120, 125 to a fluid outlet channel viafluid flow paths formed within the assembly 110. Control of the fluidflow paths can be implemented by pneumatically controlled valves formedat the interface of layers of the laminate pump assembly 100.Accordingly, some embodiments include one or more pneumatic controlpumps 130 which actuate the valves within the laminate pump assembly110.

FIG. 2 shows an implementation of a laminate pump assembly 200 accordingto some embodiments. The laminate pump assembly 200 comprises aplurality of layers 210 comprising a substantially rigid material. Someof the layers 210 can be separated by one or more thin membranes. Thelayers and membranes can be joined together in a compression fit suchthat channels formed therewithin are sealed. In some embodiments,snapping mechanisms or mechanical fasteners can be used to compress andcombine sequential layers. Alternatively, the layers can be clamped orfused together. The layer material should be selected from materialshaving high resistivity to water and chemicals used for specificembodiment. For example, in some embodiments, the layers comprise amolded plastic. In some embodiments, the layers comprise afluoropolymer, such as PVDF (KYNAR®), FPM, PTFE (Teflon®) or others.Layers or portions of layers which have no direct contact with waterand/or chemicals can be made of other materials such as acetal, PVC, orABS (acrylonitrile-butadienestyrene).

In the embodiment of FIG. 2, the assembly 200 is generally cylindricalhaving a top surface 202, a bottom surface 204, and lateral surface 206.Inlet connectors 220, 222 are shown on the top surface of the assembly200. The inlet connectors 220, 222 provide for the connection of fluidsources (e.g. a source of use composition 280) to flow paths formedwithin the assembly 200. The layers 210 include patterns of channels,bores, chambers, and other features formed on interior surfaces of thelayers 210. When the layers are aligned and joined together, thesefeatures define the flow paths. The flow paths connect the fluid inletconnectors 220, 222 to one or more outlet channels. Here, the outletchannels 230 are provided on the top surface 202 of the assembly 200 andare connected with analytical instrumentation 240 adapted to analyze thefluids.

The formation and operation of the fluid flow paths will now bediscussed with reference to FIGS. 3A-3D. FIG. 3A shows asemi-transparent, top plan view of a laminate pump assembly 300according to some embodiments indicating internal features of theassembly 300. The assembly 300 includes four flow paths 320 radiallydisposed within the five layers 301, 302, 303, 304, 305 of the assembly300. For purposes of identifying a specific one of the flow paths 320, aletter A-D will be appended to the referenced part number. Part numberreferences not including an appended letter should be construed to applyto any or all of the identified parts. Each flow path 320 comprises aninlet valve 330, a pump valve 340, and an outlet valve 350. Each valveis connected to a control manifold 371, 372, 373 which provides forconnection to pneumatic control pumps at pneumatic connection interfaces381, 382, 383.

FIGS. 3B and 3C, respectively, show a top plan view and cross-sectionalview along line C-C of a flow path 320 of the laminate pump assembly 300of FIG. 3A. The flow path 320 begins at inlet connector 321 whichprovides for connection of the fluid source to the flow path 320.Passage 322 delivers fluid from the inlet connector 321 to inlet valve330. Operation of the inlet and other valves of the flow path, will bediscussed below. When opened, the inlet valve 330, allows fluid to flowto pump valve 340 via passage 323. From the pump valve 340, fluid flowsto the outlet valve 350 via passage 324. And from the outlet valve 350,fluid flows to outlet channel 325. In this embodiment, the assembly 300includes an integral mixer 390, which connects with the outlet channels325 of each of the flow paths.

FIG. 3D shows a cross-sectional view of the laminate pump assembly 300taken along line D-D of FIG. 3A. This view shows the passages 384′,385′, 386′ which connect control manifolds 371′, 372′, 373′ withpneumatic control pump connectors 381′, 382′, 383′. In operation,pneumatic control pump connectors 381′, 382′, 383′ are connected topneumatic control pumps which pressurize or depressurize pneumaticcontrol chambers of each valve, thus controlling fluid flow within theflow paths. As can be seen in FIG. 3A, the use of control manifoldsallows valves of multiple flow paths to share a common pneumatic controlpump. For example, each of the valves of flow paths 320A and 320B haveindividual control manifolds (e.g. the valves of flow path 320A havecontrol manifolds 371A, 372A, 373A, and the valves of flow path 320B,have control manifolds 371B, 372B, 373B). Accordingly, these flow pathsare individually actuatable. Each of the valves of flow paths 320C and320D, however, share control manifolds 371′, 372′, 373′. Accordingly,flow paths 320A and 320B are individually actuatable separate from flowpaths 320C and 320D which are simultaneously actuatable.

Each of the valves 330, 340, 350 of the flow path 320 can comprise apneumatically actuated diaphragm valve such as that shown in FIGS. 4Aand 4B. A pneumatically actuated diaphragm valve 400 comprises a chamber402 formed at an interface of two layers 411, 412 of the laminate pumpassembly. A membrane 419 comprising a flexible, expandable materialdivides the chamber 401 into a pneumatic control chamber 402′ and afluid flow chamber 402″. The pneumatic control chamber 402′ includes aconnection to a pneumatic control passage 403 which connects thepneumatic control chamber 402′ with a pneumatic control pump (e.g. via acontrol manifold). The fluid flow chamber 402″ is in fluid communicationwith a fluid inlet passage 404 and a fluid outlet passage 405. Whenpressure within the pneumatic control chamber 402′ is low the fluid flowchamber 402″ is “opened” allowing for fluid to flow along the fluid path406 from fluid inlet passage 404 to fluid outlet passage 405. This canoccur, for example, by removing pneumatic fluid (for example, air) fromthe control chamber 402′, e.g. according to arrow 407. When pressurewithin the pneumatic control chamber is increased the fluid flow chamber402″ collapses, thereby preventing the flow of fluid from the fluidinlet passage 404 to the fluid outlet passage 405 and forcing any fluidwithin the fluid flow chamber 402″ out one of the passages 404, 405. Inthis state, the valve 400 is said to be “closed.” The valve 400 can beclosed, for example, by delivering pneumatic fluid to the controlchamber 402′, e.g. according to arrow 408.

In some embodiments, the chamber 402 is formed at a recessed area withina single surface layer 412. Forming the chamber 402 in this manner canreduce fabrication demands by requiring fewer and more easily performedmanufacturing techniques to be employed. Of course, the chamber can beimplemented by providing and aligning recesses in adjacent layers 411,412. Moreover, while the chambers of valves 330, 340, 350 in theembodiment of FIG. 3A are circular, the device should not be limited tosuch. For example, chambers can be square, rectangular, or otherwiseshaped. In addition, generally any acceptable method can be used tofabricate the chambers disclosed herein. For example, in someembodiments, each layer comprises molded plastic having the chambers,passages, channels, and other features molded into the part duringfabrication. Alternatively, channels and chambers can be etched andpassages can be drilled into layers once the layers have been formed.

Pneumatically actuated valves 400 further comprise a pneumaticallyactuated membrane 419 comprising a flexible film layer. In addition tobeing flexible, the membrane 419 should be resilient to fluids which thesystem will accommodate. Moreover, the membrane 419 should beimpermeable to fluids, so as to provide fluid separation between thepneumatic control chamber 402′ and the fluid flow chamber 402″. Forexample, in some embodiments the membrane 419 comprises a syntheticfluoropolymer film such as PTFE (polytetrafluoroethylene orpolytetrafluoroethene), e.g. Teflon. In addition, it is preferable thatthe membrane comprises a material and is installed such when thepneumatic control pumps are turned off, there is enough tension in themembrane to maintain the valves in a closed state. This can preventunwanted fluid flow and leakage.

The membrane 419 is positioned within the valves 400 so as to completelyseparate the pneumatic control chamber 402′ and the fluid flow chamber402″. The membrane 400 can be sized slightly larger in diameter than thechamber 402 which it divides and be clamped in place by the adjacentjoined layers 411, 412 of the assembly. Alternatively in someembodiments, such as that shown in FIG. 3C, the membrane comprises amembrane layer 420, 421 that covers substantially the entire surface ofthe layer. In such embodiments, a single membrane layer e.g. membranelayer 420, may serve as the membrane for multiple valves, i.e. inletvalve 330 and outlet valve 350. At each valve, the fused layers aboutthe membrane provide a clamping force at the borders of each chamber,thus securing the membrane in place. As needed, a membrane layer mayinclude features to allow for passages. For example, FIG. 3E shows anenlarged view of region 3E identified in FIG. 3C. At this region,passage 321 crosses the interface of layers 303, 304 that sandwich themembrane layer 421. To accommodate passage 321, the membrane layer 421includes a hole. In addition, some embodiments may include features suchas an o-ring 308 or layer protrusion 309 that prevent leakage of fluidfrom the flow path at this junction. Moreover, such leakage preventionfeatures may be provided about valve chambers or other features toprevent leakage of fluid between layers.

With reference to FIG. 3C, an activation sequence of the valves 330,340, 350 of the flow path 320 will now be described. The activationsequence shown in FIG. 5 and described below provides for the sequentialintake (aspiration) and expelling (dispensing) of fluid from each of thevalves resulting in the delivery of a predetermined, metered volume offluid from a connected fluid source to the outlet channel 325. Suchactivation sequence may be referred to as a “pump cycle” 500.

In an initial state (501), the inlet valve 330 is closed, preventingfluid flow along the flow path 320. To begin the pump cycle, the inletvalve 330 is opened (502). This draws fluid from the connected fluidsource in through passage 322 via inlet connector 321. Pump valve 340 isthen opened, while outlet valve 350 remains closed (503). The opening ofthe pump valve 340 can occur simultaneously with the opening of theinlet valve 330, or following an optional delay (504). Pump valve 340can then be held open as inlet valve 330 is closed (505). At this point,a metered volume of fluid is held within the flow path 320 at the fluidflow chamber of the pump valve 340 and passages 323, 324. Outlet valve350 can then be opened (506), connecting channel 324 with outlet channel325. With inlet valve 330 held closed, pump valve 340 can then close(507), forcing fluid out via the fluid flow path 320 through channel 324and the fluid flow path of the opened outlet valve 340 to the outletchannel 325. Outlet valve 340 can then be closed (508), returning thesystem to its original state (509).

The metered pump cycle volume of fluid dispensed via the pump cycle 500described above depends largely on the dimension of the valves andpassages. In particular, the metered volume is governed by the volume ofthe fluid flow chamber of the pump valve 340 and the volumes of passages323 and 324. In some embodiments, these features are dimensioned suchthat the pump cycle volume is less than 100 microliters. For example, insome embodiments, pump cycle volume of each flow path is approximately30 microliters. In such an embodiment, the inlet and outlet valves canhave volumes of approximately 5 microliters each, and the pump valve canhave a volume of approximately 30 microliters, for example.

Due to the small volumes being moved, and the quick action of thepneumatically actuated valves 330, 340, 350, complete pump cycles can beexecuted rapidly. For example, in some embodiments, a single pump cycle500 can occur in less than 10 seconds. In some embodiments, each pumpcycle 500 can take approximately 3 seconds, each valve actuating withinapproximately 0.5 seconds or less. Thus, each flow path can rapidlydeliver predetermined volumes of fluid.

FIGS. 10A and 10B show views of another embodiment of a flow path 1020according to some embodiments. FIG. 10A shows a top plan view of theflow path 1020, and FIG. 10B shows a cross-sectional view of the flowpath 1020 within a laminate pump assembly 1000 comprising four rigidlayers 1001, 1002, 1003, 1004 and a single membrane 1005. This flow path1020 is similar in structure and operation to that shown in FIGS. 3B and3C, however a horizontal valve arrangement (rather than a stackedarrangement) has been utilized. In this embodiment, each of the valves1030, 1040, 1050 reside at a single layer interface, i.e. the interfaceof layer 1002 and layer 1003. Accordingly, only one membrane 1005 needbe utilized. However, the horizontal valve arrangement can require alarger laminate assembly surface area in order to fit all valve chambersonto the device because it does not utilize space within the verticaldimension as does the stacked arrangement. Of course, embodiments of theinvention are not be limited to the stacked and horizontal arrangementsshown as one of ordinary skill in the art can appreciate different orcombinations of valve arrangements that can be utilized to accomplishthe purposes taught herein.

The flow path 1020 begins at inlet connector 1021 which provides forconnection of the fluid source to the flow path 1020. Passage 1022delivers fluid from the inlet connector 1021 to inlet valve 1030.Operation of the inlet and other valves of the flow path 1020, isidentical to that described above. When opened, the inlet valve 1030,allows fluid to flow to pump valve 1040 via passage 1023. In contrast tothe previously described embodiment, passage 1023 comprises a horizontalpassage contained within layer 1003. From the pump valve 1040, fluidflows to the outlet valve 1050 via passage 1024, which is also ahorizontal passage. And from the outlet valve 1050, fluid flows tooutlet channel 1025. In this embodiment, the assembly 1000 includes anintegral mixer 1060, which, as above, can connect with the outletchannels 1025 of each of a plurality of flow paths contained within asingle laminate assembly 1000.

Control of the valves 1030, 1040, 1050 can be accomplished as describedabove. Each of the valves 1030, 1040, 1050 includes a pneumatic controlpassage 1033, 1043, 1053 connectable to one or more pneumatic controlpumps. As with the devices described above, such control passages 1033,1043, 1053 can be connected with manifolds to connect two or more flowpaths. Actuation of the control paths 1020 to effectuate delivery of avolume of fluid therethrough can likewise be accomplished as describedabove, e.g. according to pump cycle 500.

In systems which process multiple flow paths in parallel (i.e., eachparallel flow path simultaneously executes a pump cycle), for example,those including control manifolds, fluid preparation of sample mixturescan occur significantly faster than previously known systems. Forexample, in a peracid/peroxide concentration monitor, sample preparationof previously existing devices took on the order of 5 minutes. Now,according to some embodiments of the present invention, the samplepreparation steps can be accomplished in less than 10 seconds, e.g.within 3 seconds. The improved sample preparation time afforded byembodiments according to the present invention can be especially usefulin use composition monitoring applications to decrease measurementsequence times. Reduced measurement sequence times can result in a usecomposition monitor that can provide more timely notification ofthreshold events.

FIGS. 3F and 3G show views of an exemplary laminate pump assembly 300Fadapted for use as a sample preparation system for a peracid/peroxideconcentration monitor. The laminate assembly 300F comprises three flowpaths 320E, 320F, 320G adapted to deliver volumes of three fluids to anintegral mixer 390. This embodiment includes two selector valves(pneumatic control valves 360E′, 360E″ within the laminate pump assembly300F) connected to a single flow path 320E so that use composition or ablank (e.g. water) can be selectively introduced depending upon whetherthe monitor is performing a “measurement cycle” or a “reagent blankcycle.” Accordingly, the inlet connectors 321E′, 321E″ of the selectorvalves 360E′, 360E″ can be connected with a source of use compositionand a source of water, respectively. The other flow paths 320F, 320G caninclude connections to a source of reagent and a source of acid. Forexample, in some embodiments, the inlet connector 321F is connected witha source of reagent (e.g. potassium iodide) and the inlet connector 321Gis connected with a source of acid (e.g. acetic acid). In the embodimentof FIG. 3F, the inlet connectors 321 have been arranged about the top ofthe laminate pump assembly 300F in a pattern and spacing identical tothat of the embodiment shown in FIG. 3. Accordingly, such devices canutilize a cartridge system such as that described with respect to FIGS.9A-9D below.

In this embodiment, each of the flow paths 320 are simultaneouslyactuatable. The laminate pump assembly 300F includes pneumatic controlmanifolds 371F, 372F, 373F for providing such simultaneous actuation.Each of the control manifolds are connectable to a pneumatic controlpump at respective pneumatic connection interfaces 381F, 382F, 383F. Asdescribed below, in some embodiments a single pneumatic control pump canbe utilized to control the actuation of valves of the flow paths 320 viaconnection to the pneumatic control interfaces 381F, 382F, 383F andpneumatic control manifolds 371F, 372F, 373F.

FIG. 3G is a cross-sectional view taken along line G-G of FIG. 3F whichillustrates a selector valve connection 320E′ to the flow path 320E. Theselector valve connection 320E′ operates based on the inclusion of aselector valve 360E′ formed within the laminate pump assembly 300F. Inthis embodiment, the selector valve comprises a pneumatic control valve360E′, which can be constructed and operate according to the pneumaticcontrol valve described with reference to FIGS. 4A and 4B. The pneumaticcontrol valve 360E′ can be formed within the layers of the laminate pumpassembly, for example, at the interface of layers 302F and 303F. Ofcourse, the pneumatic pump can be formed at other layers, provided amembrane 420 is located at such junction and so long as the selectorvalve placement does not interfere with the placement of othercomponents of the laminate pump assembly 300F.

In operation, the selector valve connection 320E′ operates much like theflow paths previously discussed. Fluid can enter the device at inletconnector 321E′ and pass through inlet passage 322E′ to the selectorvalve 360E′. The selector valve 360E′ can be controlled by a pneumaticcontrol pump which can be connected to the assembly at pneumatic controlconnection interface 387E′ which is connected to the selector valve360E′ by passage 388E′. Although the embodiment shows a directconnection between the selector valve and control connection interface,some embodiments may include one or more control manifolds to connectmultiple selector valves to a common pneumatic control source forsimultaneous actuation. The outlet of the selector valve 360E′ isconnected to passage 323E′ which provides connection to the inlet valve330E of flow path 320E. Thus, when selector valve 360E′ is open, a fluidconnection is provided from fluid inlet connector 321E′ to the flow path320E, and no such connection is provided when the selector valve 360E′is closed.

With reference to the pneumatic control pumps described below, a singlepneumatic control pump can be utilized to control the pair of selectorvalves 360E′, 360E″. For example, an inlet of a pneumatic control pumpcan be connected with the pneumatic control connection interface 387E′and the outlet of the pneumatic control pump can be connected with thepneumatic control connection interface 387E″. In such arrangement,operation of the pneumatic control pump in a first direction, forexample, opens selector valve 360E′ and closes selector valve 360E″ thusconnecting flow path 320E with the source of use composition connectedat inlet connector 321E′ (i.e. the measurement cycle is active). Whenthe pneumatic control pump is activated in the second direction,selector valve 360E′ is closed and selector valve 360E″ is opened. Thisconnects flow path 320E with the source of blank (e.g. water) connectedat inlet connector 321E″ (i.e. the reagent blank cycle is active). Thus,two pneumatic control pumps are required to control the laminate pumpassembly 300F (i.e. one to control each of the flow paths via thecontrol manifolds 371F, 372F, 373F, and one to control the selectorvalves 360E′, 360E″).

In addition, the embodiment of the laminate pump assembly 300 of FIG. 3Acan be adapted for use as a peracid/peroxide concentration monitor. Forexample, connections for the peracid/peroxide concentration monitor canbe as follows: a source of use composition can be connected with inletconnector 321A; a source of blank can be connected with inlet connector321B; a source of reagent can be connected with inlet connector 320C;and a source of acid can be connected with inlet connector 321D. Thus,the dispersion of use composition and blank can be separatelycontrolled, and the dispersion of reagent and acid can be simultaneouslycontrolled. Such operation would require the use of three pneumaticcontrol pumps (i.e. one each for flow paths 320A and 320B, and a thirdfor flow paths 320C and 320D).

When assembled, the connection inlets of each laminate pump assemblyembodiment described above (i.e. the laminate pump assembly 300 of FIG.3A, and the laminate pump assembly 300F of FIG. 3F) can resemble thelaminate pump assembly 200 of FIG. 2. That is, when assembled, thelaminate pump assembly 200 can include connection inlets 220, 222 on itstop surface 202 and control interfaces on its bottom surface 204 tofacilitate easy connection of fluid sources.

Referring back to FIG. 1, one or more pneumatic control pumps 130 can beconnected with the laminate pump assembly 110 to pneumatically controlthe pump cycle. Accordingly, the pneumatic control pumps utilized shouldbe capable of delivering pneumatic fluid to and removing pneumatic fluidfrom the laminate pump assembly 110. Preferably, the pneumatic controlfluid comprises air, however other pneumatic control fluids can beutilized. In some embodiments, for example, the pneumatic control pumps130 can comprise reversible peristaltic pumps, such as a peristalticmicro pump SP100, model SP100VO with 12 V DC-20 RPM available from APTInstruments of Rochester, Ill., USA, or an ultra small peristaltic pump,model RP-Q1 available from Takasago Electric, Inc. of Nagoya, Japan. Insome embodiments, the pneumatic fluid used to control each valvecomprises air, however other fluids may be utilized. Of course othermodels or types of pneumatic control pump can be used, such as, forexample gear pumps or syringe pumps.

Another example of a reversible pneumatic control pump 1100 is shown inFIG. 11. In this embodiment, the control pump 1100 comprises auni-directional pump 1110 and a pair of three-way electrically actuatedcontrol valves 1120. The pneumatic connectors A, B are each connectedwith an outlet 1121 of one of the electronic control valves 1120. Inlets1122, 1123 to each of the electronic control valves 1120 are connectedwith a network of tubing that allows for the direction of operation(i.e., pumping from pneumatic connector A to pneumatic connector B, orvice versa) of control pump 1100 to be controlled. For example, theuni-directional pump 1110 can comprise mini diaphragm pumpVMP1624MM-12-60-CH available from Virtual Industries, Inc., ColoradoSprings, Colo., US and the control valves 1120 can comprise, forexample, sub-miniature valve model 161TO31 available from NResearch,Inc., West Caldwell, N.J., US.

In operation, the pump 1110 turns ON when a voltage (e.g. 12 Volts) isapplied to the contacts Ground and Start. When the pump 1110 is on, itoperates in a single direction, e.g. along arrow 1130. If no voltage isapplied to the contact Direction both control valves 1120 are held inposition 1. In this position, the network of tubing is connected suchthat the pump 1110 is pumping pneumatic fluid from pneumatic connector Bto pneumatic connector A. Thus, pneumatic connector A is an output forhigh pressure and low pressure is provided at pneumatic connector B.When a voltage (e.g. 12 Volts) is applied to the contact Direction, bothcontrol valves 1120 switch to position 2. In this position, and withoutswitching the direction of operation of pump 1110, the network of tubingis connected such that the direction of pneumatic fluid flow isreversed. Accordingly, pneumatic fluid is pumped from pneumaticconnector A to pneumatic connector B. Thus, pneumatic connector B is anoutput for high pressure and the pressure at pneumatic connector A islowered.

In a simple arrangement, the pneumatic control chamber 402′ of eachvalve of each flow path can be connected with a dedicated, andseparately controllable pneumatic control pump. However, in manyembodiments, multiple pneumatic control chambers 402′ are connected viaa control manifold such that a single pneumatic control pump 130 cansimultaneously control multiple valves. Accordingly, fewer pneumaticcontrol pumps need be utilized. In addition, some pneumatic controlpumps (e.g. the peristaltic pumps described above) operate asdisplacement pumps. Displacement pumps operate by displacing pneumaticfluid from a pump inlet to a pump outlet. Reversing the direction ofpump operation, causes pneumatic fluid to be displaced from the pumpoutlet and delivered to the pump inlet. Accordingly, furtherefficiencies can be realized by selectively coupling the pump inlet andpump outlet of a reversible, displacement pump with specific pneumaticcontrol chambers.

FIG. 6 shows a schematic of how a single reversible, displacementcontrol pump 610 can be connected with the valves of a single flow path,such as that shown in FIG. 3C. The reversible displacement control pump610 can comprise any of the pneumatic control pumps discussed above, forexample, a peristaltic pump or a control pump such as that shown in FIG.11. In such an arrangement, the inlet of control pump 610 can beconnected with the pneumatic control chamber 402′ of the inlet valve330, and the pneumatic control chamber 402′ of the pump valve 340. Suchconnection can be facilitated by connecting the control pump inlet topneumatic control pump connectors 381, 383, which in turn connect tocontrol manifolds 371, 373, respectively in FIG. 3D. The control pumpoutlet can be connected with the pneumatic control chamber 402′ of theoutlet valve 350. Such connection can be facilitated by connecting thecontrol pump outlet to pneumatic control pump connector 382, which inturn connects to control manifold 372. Accordingly, a singledisplacement control pump, can be utilized to control a single flowpath, or indeed, all flow paths connected by control manifold. Forexample, with respect to FIG. 3A, two pneumatic control pumps can beutilized to control all four flow paths 320.

The connections shown in the schematic of FIG. 6 provide for operationof the flow path according to the above-described pump cycle 500. Forexample, as control pump 610 is actuated in the forward direction,pneumatic fluid is displaced from the inlet valve 330 and the pump valve340. Thus, the inlet valve 330 and pump valve 340 open (502), (503).Optionally, a delay volume 620 can be provided between the pump valve340 and the control pump 610 to provide the optional delay (504) betweenthe opening of the inlet valve 330 and the opening of the pump valve.This delay 620 can be provided, for example, by increasing the volume ofpneumatic control passage 384 with respect to pneumatic control passage385 as shown in FIG. 3D. Also, during forward pump operation, thedisplaced pneumatic fluid is delivered to outlet valve 350, ensuringthat the outlet valve 350 remains closed (503). Optionally, a filter 630can also be connected with the pump outlet to provide for leakage ofexcess pneumatic fluid.

When the control pump 610 is actuated in the reverse direction,pneumatic fluid is drawn from the outlet valve 350, thereby causing itto open (506). The displaced pneumatic fluid is delivered to the inletvalve 330 (505), and (possibly after the optional delay 620) the pumpvalve 340 (507). Thus, the inlet valve 320 is closed as the outlet valve350 is opened. Additionally, the pump valve 340 is closed, forcing fluidout through the open outlet valve 350.

The pump cycle 500 can be governed by a computer controller 160. Forexample, in some embodiments, this controller can be the same as thecontroller which is used to control the sensor and other instrumentationor it may be a dedicated controller. Indeed, a single controller can beutilized to implement a measurement or other operation sequence whichincludes the sample preparation sequence or pump cycle described above.

In some embodiments, the controller 160 can be adapted to implementmultiple operation sequences. For example, FIG. 12 shows a flow chart ofan exemplary control operation 1200 of a peracid/peroxide concentrationsensor. This control operation 1200 will be described with reference tothe laminate pump assembly 300F of FIG. 3F. The sequence begins (1201)with the system in an idle state. A user can then select which operationsequence to run (1202). In this embodiment, the control operation 1200can provide two operation sequences: a measurement sequence (1210), anda reagent blank sequence (1220). The measurement sequence (1210) can beutilized to perform an actual measurement of the peracid/peroxideconcentration of a volume of the use composition. The reagent blanksequence (1220) can be utilized to provide calibration data for thesystem which can be utilized during the measurement or other cycles.

In the measurement cycle (1210), the controller 160 manages thepreparation and measurement of a sample mixture and the calculation ofthe mixtures properties. First, the use composition input (1211) isselected. For example, with respect to the laminate pump assembly 300F,this can be accomplished by actuating selector valves 360E′, 360E″ suchthat the selector valve connected with the source of use composition isopened, while the selector valve coupled with the source of blank isclosed. A pump cycle can then be performed (1212). This can beaccomplished, for example, by performing the pump cycle 500 shown inFIG. 5. In the embodiment of FIG. 3F, when the pump cycle 500 isperformed with the use composition selector valve 360E′ open, controlmanifolds 371F, 372F, 373F allow for the simultaneous delivery of usecomposition, reagent, and acid along flow paths 320E, 320F, 320G,respectively. Further, the pump cycle causes these volumes of fluid tobe delivered via outlet channels 325 to integral mixer 390, where thefluids are mixed and delivered out of the laminate pump assembly 300F.

Once the pump cycle has been performed, the fluid mixture is stoppedwithin the sensor (1213). While within the sensor, a measurement isperformed (1214). In some embodiments, it can take approximately from 1second to 15 seconds, e.g. 5 seconds, to perform the measurement andcollect the necessary response data. The controller 160 can thencalculate the peracid/peroxide concentration based upon the responsedata (1215). The resulting concentration information can then bedelivered as the output of the system (1216). For example, theconcentration can be utilized to control an alarm or the use compositionusage in the case of a monitor. In the case of an analytical testingsystem, the determined concentration can be output, for example, to adisplay. At this point, the sequence operation is finished (1230) andthe system can be returned to the starting state.

In the reagent blank cycle (1220), the controller 160 manages thepreparation and measurement of a reagent blank. The controller thencalculates calibration data based upon the reagent blank measurementdata. In this operation, first the blank input is selected (1221). Theblank can comprise water, for example. As above, the selection of theblank can be accomplished by actuation of one or more selector valves.Then, a pump cycle can be performed (1222). The pump cycle can be thesame pump cycle 500 performed during the measurement cycle (1210),however the different connection provided to flow path 320E by theactuation of the selector valves, provides for a different mixture to beprepared. Once the mixture is prepared, it can be stopped within thesensor (1223) and a measurement can be performed (1224) just as was donein the measurement cycle (1210). Once the measurement has beenperformed, the obtained response data can be used to calculatecalibration values which can be stored in controller or other systemmemory (1225). These calibration values can later be used by thecontroller during the calculation of the peracid/peroxide concentration(1215) during the measurement cycle (1210). At this point, the sequenceoperation is finished (1230) and the system can be returned to thestarting state.

Of course, the sequence operation 1200 and cycles described herein withrespect to FIG. 12 are but one exemplary embodiment of device operationaccording to the present invention. This specification should not beread to limit the devices or methods disclosed herein to such method asall others apparent to one of ordinary skill in the art should beconsidered within the scope of invention.

Referring back to FIG. 1, the microflow analytical system 100 includesinstrumentation connected with the output channels of the laminate pumpassembly 140, 150. In some embodiments, the instrumentation comprises amixer 140 and a sensor 150. The mixer 140 can provide thorough mixing ofmetered fluid volumes dispensed by the laminate pump assembly 110. In ause composition monitor, appropriate mixing can ensure that the responsedata measured by the sensor 150 leads to an accurate determination ofthe characteristic of the use composition to be determined. The mixer140 may be implemented using any conventional device designed to rapidlymix together two or more fluids. For example, the mixer 140 may be apiece of tubing with internal baffles that cause flow reversal of thefluids to result in rapid mixing. The mixer 140 may also be implementedusing a knotted reactor, reaction coil, serpentine or other fluid mixingdevice known in the art. An example baffle-type static mixer is theSeries 120 Individual Mixing Elements available from TAH Industries Inc,Robbinsville, N.J. However, it shall be understood that any suitablemixer may be used without departing from the scope of the presentinvention, and that the invention is not limited in this respect.

In addition, some embodiments include a mixer integral with the laminatepump assembly 110. For example, the laminate pump assembly 300 shown inFIGS. 3A and 3C includes an integral mixer 390. In this embodiment, theintegral mixer 390 comprises a chamber formed within a layer 305 of thelaminate pump assembly 300. The chamber includes connections to theoutlet channels 325 of each of the flow paths 320. As fluid issimultaneously dispensed through the flow paths, it is injected into themixer chamber 390. The simultaneous injection causes rapid mixing of thefluids before they are ejected from the mixer 390 along mixer outlet391.

Mixed, or otherwise dispensed fluid can then be delivered to a sensor150. The sensor measures at least one characteristic of the fluidmixture indicative of the properties to be determined. The measurementsobtained by detector 150 are referred to herein as “response data.” Forexample, properties to be determined can be the concentrations ofperacid and/or hydrogen peroxide in a use composition. Controller 160determines the properties based on the response data. In someembodiments, the sensor 150 is an optical detector that measures thetransmittance and/or the absorbance of the fluid mixture. In suchembodiments, the response data may be the optical transmittance data oroptical absorbance data of the sample as a function of time. In otherembodiments, the sensor 150 may measure other characteristics indicativeof the particular property to be determined, such as fluorescence, pH,oxidation-reduction potential, conductivity, mass spectra and/orcombinations thereof. In such embodiments, the response data would bethe corresponding measured characteristic at the appropriate points intime. Example sensors 150 include photometric, pH, ORP, conductivity orother sensors. The photometric sensors utilized can operate in thevisible, ultraviolet or infrared wavelength range, although otherluminescence detection techniques may also be used without departingfrom the scope of the present invention. One example of a suitablecommercially available photometric detector can be assembled using aDT-MINI-2 Deuterium Tungsten Source, FIA-Z-SMA-PEEK Flow Cell andUSB4000 Miniature Fiber Optic Spectrometer, all available from OceanOptics Inc., Dunedin, Fla. It shall be understood, however, that anysuitable optical detector may be used without departing from the scopeof the present invention, and that the invention is not limited in thisrespect. Indeed, an appropriate optical sensor may be any of thosedescribed for use with respect to U.S. patent application Ser. No.12/370,369 filed Feb. 12, 2009, which is presently co-owned and isherein incorporated by reference.

An optical sensor 150 may be coupled with the laminate pump assembly 110via a length of tubing, or otherwise. For example, the cross-sectionalview of FIG. 7 shows a portion of a laminate pump assembly 710 having anoptical sensor 720 coupled directly thereto. The optical sensor 720includes a flow channel 730 passing through the sensor body. Twoemitter/detector pairs abut the flow channel 730. The emitter 740 ofeach pair emits light of a particular wavelength which is detected by acorresponding detector 750. In this embodiment, the laminate pumpassembly 710 includes an integral mixer. The integral mixer deliversmixed fluid along a mixer outlet 760 which has a thermocouple insert 770installed therein. An outlet tube 780 coupled with the sensor 720delivers the measured fluid mixture to waste 785. The thermocoupleinsert 770 thermally links the optical sensor 720 (which is in directcontact with the thermocouple insert 770) with the mixer outlet 760 suchthat fluid passing through the mixer outlet is thermally adjusted basedupon the temperature of the sensor 720. Such an arrangement allows forstabilization of fluid temperature and reduced variance in sensorperformance. Some embodiments optionally include a temperaturecontrolled environment 790 surrounding the sensor 720. The temperaturecontrolled environment can comprise, for example, those as described inU.S. patent application Ser. No. 12/370,348 filed Feb. 12, 2009, whichis presently co-owned and is herein incorporated by reference.

FIG. 8, shows yet another embodiment, where the sensor 820 has beenincorporated into the laminate pump assembly 800. In this embodiment, athermocouple insert 870 having opposing ports for receiving opticalfibers 842, 852 is installed within the outlet channel 891 from anintegral mixer 890 of the laminate pump assembly 800. An emitter 840coupled with one of the optical fibers 842 and a detector 850 coupledwith the other optical fiber 852 provide the sensor functionality. Inthis embodiment, a thermoelectric device 860 including a central port862 has been coupled with the thermocouple 870. The thermoelectricdevice 860 can comprise, for example, a Peltier device which can providefor heating and/or cooling of the thermocouple insert 870. Thethermocouple insert 870 can thus be utilized to regulate the temperaturewithin the sensor.

An advantage of systems according to some embodiments of the presentinvention is that temperature stabilization can be facilitated easierthan in other embodiments. This is because laminate pump assembliesaccording to embodiments of the invention enable the delivery of smallquantities of fluids (e.g. less than 100 microliters). These smallervolumes of fluid can be temperature adjusted significantly more rapidlythan larger volumes of fluid.

In the case of an optical sensor, the voltage response of the sensorcorresponds to the amount of the light transmitted through the samplemixture. The sensor thus essentially measures the change of the samplesolution optical properties within the sensor as a function of time. Thetransmittance is the ratio of the intensity of light coming out of thesample (I) to intensity of light incident to the sample (I₀), T=I/I₀.Once the transmittance of the sample is measured, the absorbance (A) ofthe sample may be calculated. The absorbance or optical density (A) is alogarithmic function of the transmittance; A=−log₁₀T=−log₁₀I/I₀=log₁₀I₀/I. With respect to embodiments used to determine the concentrationsof peracid and peroxide within a use composition, as is discussed infurther detail below, the initial absorbance of the sample (A₀) isindicative of the concentration of peracid in the use composition andthe sample absorbance variation over time is indicative of theconcentration of hydrogen peroxide in the use composition. However, asis further indicated, this relationship may not hold true across wideranging use composition concentrations. For example, at higherconcentrations, e.g. above 500 ppm peracid, concentration of peracid isa function of both initial absorbance and, to a lesser degree,absorbance over time. Accordingly, to provide instruments capable ofaccommodating use with a wide concentration range, i.e. a rangeencompassing both concentration ranges described above, alternativemethods must be utilized.

Additionally, the wavelength tested by the optical sensor can beselected based upon the particular application of the microflowanalytical system. Indeed, some embodiments include sensorsincorporating emitters of multiple wavelengths. With respect toperacid/peroxide concentration determination, wavelength selection isbased on the spectral response of the triiodide complex, and may bewithin the range of 350 to 450 nanometers, for example. A two wavelengthsystem may utilize the wavelengths 375 nanometers and 405 nanometers,for example.

As indicated above, some embodiments of microflow analytical systems areoptimized for use as an on site use composition monitor. That is, thereis a need for accurate and reliable sensors to measure use compositionproperties e.g. peracid and peroxide concentrations, when ambienttemperature can vary in wide range. Unstable temperature inside of asystem has been found to contribute to random variations inconcentration readings. Potential causes of such temperature instabilityinclude environmental temperature variances and locally generated heatand air flow from components of the measurement system such as pumps,step motors, and electronic components, such as, the controller. Thus,some embodiments include additional features to adjust the temperatureof the fluid mixture within the sensor or prior to reaching the sensor.In addition, systems according to some embodiments provide means foradjusting or stabilizing the temperature of sample prior to delivery tothe detector to avoid the inconsistencies associated with in fieldoperation.

Referring back to FIG. 1, the microflow analytical system 100 furthercomprises a plurality of sources of fluids. For example, in aperacid/peroxide concentration monitor, a connection to a source of usecomposition which contains a peracid and a peroxide as well asconnections to reagent (e.g. potassium iodide) and an acid (e.g. aceticacid) are provided. Additionally, a source of water, for preparation ofreagent blank may also be provided. In the case of a use compositionmonitor, the source of use composition can be connected to the laminatepump assembly by a length of tubing. Preferably, the length of tubingwill be as short as possible, so that the monitor can draw from usecomposition representing fresh product currently being used. Other,components, e.g. reagents, acids, water, can be provided from areservoir containing a volume of the fluid component. For example, insome embodiments, a bag reservoir containing the fluid component can beprovided. The bag reservoir can include a puncturable interface whichcan be punctured by a needle connector input 220 (see e.g. FIG. 2). Inany case, the connections to the fluid sources should be substantiallyair tight, so as to prevent air bubbles from entering the system. Airbubbles within the system can prevent the accurate metering of fluidthrough the flow paths. Fluid mixtures containing inaccurate volumes ofthe fluid components, can result in false positive measurement readings.

FIG. 9A shows an example of a disposable bag reservoir 900 according tosome embodiments. The bag reservoir 900 comprises a sealed bag 910adapted to hold a volume of the fluid. The sealed bag 910 can comprise ametalized plastic which can provide protection from ambient light. Thebag reservoir 900 includes an extended neck portion 920 having apuncturable interface 925 which is hermetically sealed after the bag isfilled with fluid. The extended neck portion 920 of the fluid bag 900can include a groove 928 for locking the bag in place about theconnection input or within a cartridge. FIG. 9B is a partialcross-sectional view of the extended neck portion 920 of the bagreservoir of FIG. 9A.

In some embodiments, the laminate pump assembly can be adapted toreceive a cartridge comprising a fluid source for one or more of thefluids. An exemplary cartridge for three disposable bag reservoirs isshown in FIGS. 9C and 9D. The cartridge 930 comprises a rectangularshell 935 having a 90 degree cutout and three rectangular compartments936. Each compartment 936 is adapted to receive a bag reservoir (e.g.,the bag reservoir 900 of FIG. 9A) and includes an opening 937 in thebottom of the shell 938 to access the bag reservoirs. In someembodiments, the opening 937 can receive an extended neck portion 920 ofthe bag reservoir 900. The bottom part of the cartridge 930 can furthercomprise an attachment plate 940 and locking member 950 having openings947, 957 that can be aligned with the openings 937 within the bottom ofthe shell 935. The lock member 950 can be received between the bottom ofthe shell 938 and the attachment plate 940 such that it can be rotatedwith limited range about a vertical axis. The lock member 950 has threeopenings 957 each with a round opening and an extension slit. In onerotational position, the round opening of each opening 957 of the lockmember is between corresponding openings 937, 957 in the bottom of theshell 938 and the attachment plate 940. In such position, each fluid bagreservoir can be placed in corresponding compartments of the cartridge936 with the extended neck portion turned down. The extended neckportion of each fluid bag extends through the openings in the bottom ofthe shell 937 and the attachment plate 947, and the opening in the lockmember 957. The lock member can then be rotated to a second position,where the narrow slit is interlocked with the groove 928 on the neck 920of the fluid bag reservoir 900. A tab 960 on the locking member 950 canprotrude through a slot 965 within the attachment plate 940 to allow forsuch rotation. In such position all fluid bags are secured in thecartridge. In another embodiment, openings in each compartment of thecartridge 937 could have different shapes each corresponding to theshape of the extended neck portion of certain of the bag reservoirs toeliminate the possibility of mistake in the bag placement in thecartridge compartments.

Each of fluid bags shown on FIG. 9A has can contain approximately 200 mlof fluid. In some embodiments, such a volume can be sufficient forapproximately 2000 analytical cycles. Once a bag reservoir has beenemptied, (or after a predetermined number of measurement cycles, e.g.2000) the cartridge can be removed from the laminate pump assembly and abag reservoir or the entire cartridge can be replaced.

The use of a cartridge can make the fluid replacement operation easy andefficient. For example, in some embodiments, the laminate pump assemblycan include guides such that the cartridge can be inserted in only acertain manner such that the puncturable interfaces of each bag areautomatically aligned with the corresponding needle connector. Thuschanging the fluid reservoirs can be as simple as inserting thecartridge and pressing down.

Referring back to FIG. 1, some embodiments further comprise a disposablewaste bag connected with the waste line 170. The disposable waste bagcan be placed under the laminate pump assembly to receive waste fluidonce analysis has been performed. The disposable waste bag can furtherinclude a puncturable interface and can be secured under the laminatepump assembly with the extended neck portion oriented up. The baginterface should be punctured by a needle connector connected to thewaste line 170 to maintain the airtight connection of the system.Embodiments including the three bag cartridge 930 shown in FIGS. 9C and9D should include a disposable waste bag having a volume of at leastapproximately 850 ml. Initially the waste bag is empty. After 2000analytical cycles it has approximately 800 ml of waste. The bag andwaste can then be discarded and replaced with a new empty waste bag.This can be performed when the cartridge is refilled or replaced.

As used herein, the term “peracid” refers to any acid that in which thehydroxyl group (—OH) is replaced with the peroxy group (—OOH). Theperacid(s) may be C2—C18 peracid(s), such as C2 (peracetic) acid and C8(peroctanoic) acid. It shall be understood that the apparatus and/ormethods of the present invention may detect the combined presence of allperacids in a sample, whether the sample contains one or more than onedifferent peracids, and that the invention is not limited in thisrespect.

Peroxycarboxylic acids generally have the formula R(CO₃ H)_(n). In someembodiments, the R may be an alkyl, arylalkyl, cycloalkyl, aromatic orheterocyclic group, and n may be one or two.

Peroxycarboxylic acids useful in this invention include peroxyformic,peroxyacetic, peroxypropionic, peroxybutanoic, peroxypentanoic,peroxyhexanoic, peroxyheptanoic, peroxyoctanoic, peroxynonanoic,peroxydecanoic, peroxylactic, peroxymaleic, peroxyascorbic,peroxyhydroxyacetic, peroxyoxalic, peroxymalonic, peroxysuccinic,peroxyglutaric, peroxyadipic, peroxypimelic and peroxysubric acid andmixtures thereof as well others known to those of skill in the art.

The concentrations of peracid and/or peroxide determined by usecomposition monitor may be used, for example, as feedback to controllerto maintain the peracid concentration in the use composition within apredefined range and/or to cause the emptying of the use compositionvessel and production of a new use composition when the hydrogenperoxide concentration exceeds the maximum peroxide thresholdconcentration. If, for example, the concentration of peracid in the usecomposition decreases below a predetermined level, the use compositionmay be replenished by adding a concentrated peracid composition to theuse composition. As another example, if the concentration of peroxide inthe use composition exceeds a predetermined level, the use compositionmay be replenished by emptying the use composition vessel of the spentuse composition and generating a new use composition.

Use compositions including peracids and peroxides described herein maybe used for a variety of domestic or industrial applications, e.g., toreduce microbial or viral populations on a surface or object or in abody or stream of water. The compositions may be applied in a variety ofareas including kitchens, bathrooms, factories, hospitals, dentaloffices and food plants, and may be applied to a variety of hard or softsurfaces having smooth, irregular or porous topography. Suitable hardsurfaces include, for example, architectural surfaces (e.g., floors,walls, windows, sinks, tables, counters and signs); eating utensils;hard-surface medical or surgical instruments and devices; andhard-surface packaging. Such hard surfaces may be made from a variety ofmaterials including, for example, ceramic, metal, glass, wood or hardplastic. Suitable soft surfaces include, for example paper; filtermedia, hospital and surgical linens and garments; soft-surface medicalor surgical instruments and devices; and soft-surface packaging. Suchsoft surfaces may be made from a variety of materials including, forexample, paper, fiber, woven or non-woven fabric, soft plastics andelastomers. The compositions may also be applied to soft surfaces suchas food and skin (e.g., a hand). The use compositions may be employed asa foaming or non-foaming environmental sanitizer or disinfectant.

The compositions may be included in products such as sterilants,sanitizers, disinfectants, preservatives, deodorizers, antiseptics,fungicides, germicides, sporicides, virucides, detergents, bleaches,hard surface cleaners, hand soaps, waterless hand sanitizers, and pre-or post-surgical scrubs.

The compositions may also be used in veterinary products such asmammalian skin treatments or in products for sanitizing or disinfectinganimal enclosures, pens, watering stations, and veterinary treatmentareas such as inspection tables and operation rooms. The compositionsmay be employed in an antimicrobial foot bath for livestock or people.

The compositions may be employed for reducing the population ofpathogenic microorganisms, such as pathogens of humans, animals, and thelike. The compositions may exhibit activity against pathogens includingfungi, molds, bacteria, spores, and viruses, for example, S. aureus, E.coli, Streptococci, Legionella, Pseudomonas aeruginosa, mycobacteria,tuberculosis, phages, or the like. Such pathogens may cause a varietiesof diseases and disorders, including Mastitis or other mammalian milkingdiseases, tuberculosis, and the like. The compositions may reduce thepopulation of microorganisms on skin or other external or mucosalsurfaces of an animal. In addition, the compositions may kill pathogenicmicroorganisms that spread through transfer by water, air, or a surfacesubstrate. The composition need only be applied to the skin, otherexternal or mucosal surfaces of an animal water, air, or surface.

The compositions may also be used on foods and plant species to reducesurface microbial populations; used at manufacturing or processing siteshandling such foods and plant species; or used to treat process watersaround such sites. For example, the compositions may be used on foodtransport lines (e.g., as belt sprays); boot and hand-wash dip-pans;food storage facilities; anti-spoilage air circulation systems;refrigeration and cooler equipment; beverage chillers and warmers,blanchers, cutting boards, third sink areas, and meat chillers orscalding devices. The compositions may be used to treat producetransport waters such as those found in flumes, pipe transports,cutters, slicers, blanchers, retort systems, washers, and the like.Particular foodstuffs that may be treated with compositions includeeggs, meats, seeds, leaves, fruits and vegetables. Particular plantsurfaces include both harvested and growing leaves, roots, seeds, skinsor shells, stems, stalks, tubers, corms, fruit, and the like. Thecompositions may also be used to treat animal carcasses to reduce bothpathogenic and non-pathogenic microbial levels.

The composition may be useful in the cleaning or sanitizing ofcontainers, processing facilities, or equipment in the food service orfood processing industries. The compositions may be used on foodpackaging materials and equipment, including for cold or hot asepticpackaging. Examples of process facilities in which the compositions maybe employed include a milk line dairy, a continuous brewing system, foodprocessing lines such as pumpable food systems and beverage lines, etc.Food service wares may be disinfected with the compositions. Forexample, the compositions may also be used on or in ware wash machines,dishware, bottle washers, bottle chillers, warmers, third sink washers,cutting areas (e.g., water knives, slicers, cutters and saws) and eggwashers. Particular treatable surfaces include packaging such ascartons, bottles, films and resins; dish ware such as glasses, plates,utensils, pots and pans; ware wash machines; exposed food preparationarea surfaces such as sinks, counters, tables, floors and walls;processing equipment such as tanks, vats, lines, pumps and hoses (e.g.,dairy processing equipment for processing milk, cheese, ice cream andother dairy products); and transportation vehicles. Containers includeglass bottles, PVC or polyolefin film sacks, cans, polyester, PEN or PETbottles of various volumes (100 ml to 2 liter, etc.), one gallon milkcontainers, paper board juice or milk containers, etc.

The compositions may also be used on or in other industrial equipmentand in other industrial process streams such as heaters, cooling towers,boilers, retort waters, rinse waters, aseptic packaging wash waters, andthe like. The compositions may be used to treat microbes and odors inrecreational waters such as in pools, spas, recreational flumes andwater slides, fountains, and the like.

A filter containing a composition may reduce the population ofmicroorganisms in air and liquids. Such a filter may remove water andair-born pathogens such as Legionella.

The compositions may be employed for reducing the population ofmicrobes, fruit flies, or other insect larva on a drain or othersurface.

The compositions may also be employed by dipping food processingequipment into the use solution, soaking the equipment for a timesufficient to sanitize the equipment, and wiping or draining excesssolution off the equipment. The compositions may be further employed byspraying or wiping food processing surfaces with the use solution,keeping the surfaces wet for a time sufficient to sanitize the surfaces,and removing excess solution by wiping, draining vertically, vacuuming,etc.

The compositions may also be used in a method of sanitizing hardsurfaces such as institutional type equipment, utensils, dishes, healthcare equipment or tools, and other hard surfaces. The composition mayalso be employed in sanitizing clothing items or fabrics which havebecome contaminated. The composition is contacted with any contaminatedsurfaces or items at use temperatures in the range of about 4° C. to 60°C., for a period of time effective to sanitize, disinfect, or sterilizethe surface or item. For example, the composition may be injected intothe wash or rinse water of a laundry machine and contacted withcontaminated fabric for a time sufficient to sanitize the fabric. Excesscomposition may be removed by rinsing or centrifuging the fabric.

The compositions may be applied to microbes or to soiled or cleanedsurfaces using a variety of methods. These methods may operate on anobject, surface, in a body or stream of water or a gas, or the like, bycontacting the object, surface, body, or stream with a composition.Contacting may include any of numerous methods for applying acomposition, such as spraying the composition, immersing the object inthe composition, foam or gel treating the object with the composition,or a combination thereof.

The composition may be employed for bleaching pulp. The compositions maybe employed for waste treatment. Such a composition may include addedbleaching agent.

Other hard surface cleaning applications for the compositions includeclean-in-place systems (CIP), clean-out-of-place systems (COP),washer-decontaminators, sterilizers, textile laundry machines, ultra andnano-filtration systems and indoor air filters. COP systems may includereadily accessible systems including wash tanks, soaking vessels, mopbuckets, holding tanks, scrub sinks, vehicle parts washers,non-continuous batch washers and systems, and the like.

The peracid/peroxide use composition monitors described above determinethe concentrations of peracid and/or hydrogen peroxide in the usecomposition using a kinetic assay procedure. This is accomplished byexploiting the difference in reaction rates between peracid and hydrogenperoxide when using, for example, a buffered iodide reagent todifferentiate peracid and hydrogen peroxide concentrations when boththese analyte compounds are present in the use composition. The usecomposition monitor may also determine the concentrations of peracidand/or hydrogen peroxide in the presence of other additionalingredients, such as acidulants, one or more stabilizing agents,nonionic surfactants, semi-polar nonionic surfactants, anionicsurfactants, amphoteric or ampholytic surfactants, adjuvants, solvents,additional antimicrobial agents or other ingredients which may bepresent in the use composition.

In a use composition including hydrogen peroxide and a peracid such asperoxyacetic acid, a buffered iodide changes color as it is oxidized byboth the peroxyacetic acid and the hydrogen peroxide to form triiodideion. However, as the peroxyacetic acid and the hydrogen peroxide in theuse composition compete for the available iodide ions, reaction with theperoxyacetic acid proceeds at a faster rate than the reaction with thehydrogen peroxide, as shown in the following equations:

2CH₃COOOH+(excess)I⁻→I₃ ⁻+2CH₃COOH FASTER

H₂O₂+(excess)I⁻+2H⁺→I₃ ³¹ +2 H₂O SLOWER

This difference in reaction rates may be exploited to differentiateperacid and hydrogen peroxide concentrations when both these analytecompounds are present in the use composition. An example reaction isdescribed below and the results illustrated in FIGS. 3A-3D. It shall beunderstood, however, that the example below is for illustrative purposesonly and that the invention is not limited to the particular reactionchemistry described in the example below, and that the invention is notlimited in this respect.

Thus, embodiments of the microflow analytical system are disclosed.Although the present invention has been described in considerable detailwith reference to certain disclosed embodiments, in particular a usecomposition monitor the concentrations of a peracid and peroxide withina use composition, the disclosed embodiments are presented for purposesof illustration and not limitation and other embodiments of theinvention are possible. For example, microflow analytical systems asdisclosed herein, can be readily adapted for use in other analyticalapplications. One skilled in the art will appreciate that variouschanges, adaptations, and modifications may be made without departingfrom the spirit of the invention and the scope of the appended claims.

1-21. (canceled)
 22. A laminate pump assembly comprising: a plurality oflayers that define an inlet valve, a pump valve, an outlet valve, and aflow path extending through the inlet valve, the pump valve and theoutlet valve, wherein the inlet valve, the pump valve and the outletvalve each comprise a chamber formed at the interface of two layers ofthe plurality of layers and a membrane dividing the chamber so as todefine a fluid flow chamber and a control chamber, the control chamberbeing configured to expand in response to a control fluid entering thecontrol chamber and collapse in response to the control fluid exitingthe control chamber; an inlet connector; and an outlet channel, whereinthe inlet valve is connected to selectively provide fluid communicationbetween the inlet connector and the pump valve, and the outlet valve isconnected to selectively provide fluid communication between the pumpvalve and the outlet channel.
 23. The laminate pump assembly of claim22, further comprising a mixer connected downstream of the outlet valve.24. The laminate pump assembly of claim 23, wherein the mixer comprisesa mixing chamber formed within at least one layer of the plurality oflayers.
 25. The laminate pump assembly of claim 22, further comprisingan optical sensor configured to measure an optical characteristic of afluid flowing through the flow path.
 26. The laminate pump assembly ofclaim 25, wherein at least a portion of the optical sensor isincorporated into at least one of the layers of the plurality of layers.27. The laminate pump assembly of claim 22, wherein the plurality oflayers comprise a substantially rigid material.
 28. The laminate pumpassembly of claim 27, wherein the membrane comprises a fluoropolymer.29. The laminate pump assembly of claim 22, further comprising apneumatic control pump configured to inject a pneumatic control fluidinto the control chamber so as to expand the control chamber and therebyclose the fluid flow chamber.
 30. The laminate pump assembly of claim29, wherein the pneumatic control pump is further configured to withdrawthe pneumatic control fluid from the control chamber so as to collapsethe control chamber and thereby open the fluid flow chamber.
 31. Thelaminate pump assembly of claim 22, wherein the chamber of the inletvalve, the chamber of the pump valve, and the chamber of the outletvalve are each formed at the interface of the same two layers of theplurality of layers.
 32. A method comprising: introducing a fluid into aflow path of a laminate pump assembly, wherein the laminate pumpassembly comprises a plurality of layers that define an inlet valve, apump valve, an outlet valve, and the flow path, and wherein the inletvalve, the pump valve and the outlet valve each comprise a chamberformed at the interface of two layers of the plurality of layers and amembrane dividing the chamber so as to define a fluid flow chamber and acontrol chamber; introducing a control fluid into the control chamber ofat least one of the inlet valve, the pump valve and outlet valve so asto expand the control chamber and close the fluid flow chamber; andwithdrawing the control fluid from the control chamber of the at leastone of the inlet valve, the pump valve and outlet valve so as tocollapse the control chamber and open the fluid flow chamber, whereinthe inlet valve is connected to selectively provide fluid communicationbetween an inlet connector and the pump valve, and the outlet valve isconnected to selectively provide fluid communication between the pumpvalve and an outlet channel.
 33. The method of claim 32, wherein thefluid comprises a use composition that includes a peracid and aperoxide.
 34. The method of claim 32, further comprising mixing thefluid downstream of the outlet valve.
 35. The method of claim 34,wherein mixing the fluid comprises passing the fluid through a mixingchamber formed within at least one layer of the plurality of layers. 36.The method of claim 32, further comprising measuring an opticalcharacteristic of a fluid flowing through the flow path.
 37. The methodof claim 36, wherein measuring the optical characteristic comprisesmeasuring the optical characteristic via an optical sensor at leastpartially incorporated into a layer of the plurality of layers.
 38. Themethod of claim 32, wherein the plurality of layers comprise asubstantially rigid material.
 39. The method of claim 32, wherein themembrane comprises a fluoropolymer.
 40. The method of claim 32, whereinintroducing the control fluid into the control chamber comprisesactivating a pneumatic control pump so as to introduce a pneumaticcontrol fluid into the control chamber.
 41. The method of claim 40,wherein withdrawing the control fluid from the control chamber comprisesactivating the pneumatic control pump so as to withdraw the controlfluid from the control chamber.